Toy building brick



FIG. 1 is a front, right side, and top perspective view of a toy building brick showing the new design;

FIG. 2 is a front elevation view thereof;

FIG. 3 is a rear elevation view thereof; and,

FIG. 4 is a right side elevation view thereof, wherein the left side appears as a mirror image.

The broken lines are for the purpose of illustrating portions of the article that form no part of the claimed design. 

CLAIM The ornamental design for a toy building brick, as shown and described. 